1. Field of the Invention
The present invention relates to a positioning control method, a positioning device, and a storage medium.
In the related art, there are known GPS loggers for logging the locations of terminals by performing GPS-based positioning.
Such a GPS logger has a small size, and uses a battery having small capacity; and may be required to perform logging for a long time. However, since a GPS-signal receiving operation requires a large amount of electricity as much as several tens mW, if the GPS logger consecutively performs the GPS-signal receiving operation, the life of the battery shortens. For this reason, GPS loggers configured to intermittently perform a GPS-signal receiving operation in order to suppress the power consumption are used (see JP-A-2001-74826 and JP-B-5614548).
However, in order to always maintain a short-time positioning (so-called hot start) mode for receiving a signal within several seconds, in view of various situations, such as cases where positioning is impossible due to poor signal reception conditions, and cases where new satellites appear it is required to intermittently and sequentially perform signal reception for about 1 minute to 3 minutes at intervals of about 30 minutes. Otherwise, it is impossible to always update ephemerides necessary for short-time positioning, and the lives of batteries are greatly influenced. Also, in a case of acquiring an ephemeris by actual measurement, only the ephemerides of satellites visible from such a GPS logger are acquired. Therefore, after updating of the ephemerides, even though a new satellite appears, the new satellite cannot be used for short-time positioning, and thus influences the accuracy of positioning. Also, this situation is not limited to a GPS, and is common to other positioning systems such as GLONASS of Russia, Galileo of Europe, and Beidou of China.